| 摘要 |
PURPOSE:To execute speedy sense operation by separately controlling the gate voltages of the transfer gate MOSFET by causing the gate voltage to follow the electric potential of the opposite data lines respectively. CONSTITUTION:Respective drains of the driver MOSFET-Q17 and Q18 are connected through the transfer gates Q19 and Q20 to the bit lines L5 and L6, and the gates of switching MOSFET-Q21 and Q22 are controlled by the electric potential of the bit lines L6 and L5. When the electric potential difference between the nodes J and K exceeds the threshold level of Q21 during sense operation, the Q21 is conducted, the electric potential of the node N drops to VSS following the electric potential of the node J and the conductance of Q20 drastically decreases, thereby suppressing the lowering of the high level side node K level. As a result of the sense operation, Q20 will not be conducted, unless beta11 reaches the Q20 threshold level voltage, even when the node M electric potential becomes Vcc-beta11. Since Q22 is in the non-conduction state, Q19 is kept in the state of conduction with greater conductance and the bit line L5 is speedily discharged. |
